This invention relates to improvements in a sheet feeding control device for use in a coin wrapping machine.
Since the invention is accomplished by providing a sheet feeding device like that of a conventional coin wrapping machine with a sensor for detecting a wrapping sheet in its passage adjacent wrapping rollers and with an associated electrical circuit for controlling the feeding of the wrapping sheet the conventional machine of the type which the invention is based on will first be explained with reference to FIG. 1 showing an embodiment of the invention, which mechanically is substantially the same as the conventional machine except for a sensor.
As shown in FIG. 1, in the conventional machine, when counted and accumulated coins 1 are transferred to a wrapping position among three wrapping rollers 2, 2 and 2, a cam mechanism, not shown, is actuated to move the wrapping rollers 2, 2 and 2 from positions as shown in dotted lines to positions as shown in solid lines where the wrapping rollers pinch the accumulated coins. The leading end of a wrapping sheet 3 is fed between the wrapping rollers and the coins before the wrapping rollers completely pinch or hold the coins 1. After the completion of the pinching, the wrapping sheet 3 is wound about the coins 1 through rotation of the wrapping rollers 2, 2 and 2. Then, the sheet is pulled between a sheet feeding roller 6 for driving the sheet and the wrapping rollers 2, 2 and 2 due to a difference in their peripheral speeds and is, therefore, pushed against a cutter 4 so as to be cut. Thereafter, a pair of crimping claws, not shown, are actuated to crimp the wound sheet at opposite ends thereof. As to the wrapping operation, in view of various points it is preferred that the coins be wrapped with the sheet by two turns. In consideration of this, in case that various coins which have great difference in their diameters are to be handled, the cutter 4 should vary with its position in accordance with each kind or diameter of coins so as to adjust the cut length of the sheet 3 to the diameter of the coin. For this purpose, the cutter may be located, for example, at positions 4a, 4b, 4c or 4d in order of decreasing cut length of the sheet. That is, the cutter 4 and the paper feed 6 move as a unit around a pivot (shown at the right side of FIG. 1).
Furthermore, attendent on variation of the cutter's position, it is necessary to vary the feeding period of the sheet or the driving period of the sheet feeding roller 6 and the timing for starting to feed the sheet in accordance with the kinds of coins. In the conventional machine, these variations are accomplished by a combination of a timing cam and microswitches associated therewith or the provision of a delay circuit for delaying an output obtained from the timing cam.
However, in the above-mentioned construction, since the distances between the wrapping rollers and the cutter's positions 4a, 4b, 4c and 4d are very long, the feeding of the sheet is liable to be subject to the drifting of the rotational speed of the sheet feeding roller 6 or the load of the rolled sheet before the leading end of the sheet 3 enters the wrapping rollers 2, 2 and 2. Consequently, it is difficult to obtain a stable feeding of a predetermined length of the sheet.